Machine for rounding the edges of sheets



July-29,1930. wowEN 1,771,417

MACHINE FOR ROUNDING THEEDGES OF' SHEETS 'Filed June 22. 1929 4 'sheets-she@ 1 INVENTCR Ju1y29,193o. OWEN 1,771,417

MACHINE FOR ROUNDING THE EDGES 0F SHEETS Filed June 22, 1929 4 sheets-sheet 2 INVENTOR 4 shams-sheet 3 sunllllll l IIIHII Il Awl||||||||LL Juy 29, 1930.

K w. owEN MACHINE FOR ROUNDING THE EDGES 0F SHEETS Filed June 22. 1929 July 29, 1930. w, OWEN 1,771,417

l MACHINE FOR ROUNDING THE EDGES OF SHEETS v Filed June,` 22. 1929 4 sheets-sheet 4 f-Ei 1?` INVENTOR Patented July .29, 1930 y UNITED STATES" PATENT OFFICE- WILLIAM OWEN, OF PI'JE'JTBIB'URG'H,4 PENNSYLVANIA, ASSIGNOB TO PITTSBURGH PLATE l GLASS COMPANY, A CORPORATION F PENNSYLVANIA MACHINE FOR ROUNDING THE EDGES OF SHEETS Application lied June 22,

The invention relates to a machine for rounding edges of sheets of material by abrasive action; and is designed particularly for rounding the lower edges o f windshields which are cut on a curve; and made of com-v posite vglass,'although the machine will operate with equal success upon straight edges and upon the edges of shields made of ordinary plate or window glass. VThe object of the invention is to provide a machine-of cheap, simple construction, which will round the edges rapidly and economically. Certain embodiments of the invention are illustrated in the accompanying drawings, wherein:

Figure 1 is a plan View of the machine. Fig. 2 is a side elevation. Fig. 3 is a section on the line III-III of Fig. 2. Fig. 4 is a detail side elevation on an enlarged scale. And Figs. 5 and 6 are side elevations of modifications:

Referringto the drawings, 1 is a base or standard carrying the frame and the side beams 2*.1, 2 of angular section. On the ends of the beams,2, 2** are mounted the shafts 3, 4 carrying the pulleys 5 and 6 on which is mounted the abrasive belt 7. This belt is of canvas or yother strong, flexible materialhaving the outer face covered with a powdered abrasive, such as carborundum.r The shaft 3 is driven from the motor 8 by means of a chain 9 passing around sprockets on the motor shaft and the shaft 3. The belt is tightened by moving the bea-rings 10, 1() carrying the shaft 4 to the right by means ofthe screws 11, 11.

Lying beneath the upper Hight ofthe belt is the table 12 supported on the cross beams 2, 2. As indicated in Fig. 3, this table is curved or crowned transversely of the belt to correspond with the curvature ofthe lower edges ofthe sheets 14, which are to be rounded, so that when the belt is made to engage the table, it has the same curvature asthe table. In the constructionof Figs. 1'-'to .4 the belt is made to follow the curveof the table by the weight 0f the sheets 14 and by the two pairs of wheels 15 and 16, 16 carried ,upon axles pivoted to the blocks 17 17, 17 17 such blocks being carried by the ends of the cross beams 2. 2.

edges by 1929. Serial No. 378,'981. v

These Wheels are relatively heavy and are y preferably provided with rubber tires.

The sheets 14 show edges that are tobe rounded are positioned transversely of the belt above the .table (Fig. 1) and rest by y gravity upon the belt. Their lower edges are held against movement in the line of travel of the belt by notches in the bars 18, 18 bolted to the blocks 17-17 near the top of the table 12 along its side edges. This engagement of the sheet the notches is relatively loose so that the plates are free to rock'back and forth. Engaging the upper edges ofthe sheets at the centers thereof is the rocking bar 19, such bar being provided with the notches 20 (Fig. 4) into which the edges'of the sheets fit. The bar is reciprocated back and forth by means of an arm 21 (Fig. 1 pivoted at 22 upon the upper end of a stan ard 23 which in turn is carried by the end of one of the beams 2a. The arm 21 is oscillated by a connecting rod 24 with which it has a ball joint connection 25 at one end, the other end of such rod being pivoted to the crank disc 26. The crank disc is keyed to a shaft 27 journalled in a bearing at the upper end of a standard 28, such standard being carried by one of the beams 2. The shaft 27 1s provided with a sprocket 29 driven from the shaft 3 by a chain. 30 passing around a sprocket on such shaft. i

' The arm 21 carries a weight 31 which serves to increase the pressure between the edges of the sheet and the surface of the belt and thus increases the abrading action. The arm is provided with an extension or handle 32 by means of which the member 19 is raised to release the glass.v This handle may also be used to rock the sheets by hand, the connection with the connecting rod 24 at' the ball joint 25 being of course released at such time. If desired the glass sheets can be supported .at an inclination, instead of being placed at operation a dust co lector 33 is provided at the left end of the machine, asindicated in Fig. 2, the end of such collector being connected to an exhaust pipe 34 provided with a suitable fan,

In operation, the glass sheets 14 are positioned, as indicated in the drawings` with Fig. 4. This rounds the edges of the sheets to the approximate contour indicated at The labor cost incident to this operation isA low due to the fact that a considerable number of sheets can be smoothed at one time, and the operating cost is also low, the largest item of expense being involved in the replacement of the belts. The construction of the machine (Fig. 3) supported entirely from one side, permits the readx` removal and application of the endless belts.

Fig. 5 illustrates a modification in which the pulleys 36, 36 take the place of the table 12 in the machine of Figs. 1 to 4. These pulleys are tapered on a curve from their centers to their ends so that they give the belt substantially theV same curvature as that given by the table 12. In other respects the construction is the same as that of Figs. l to 4.

Fig. 6 illustrates another modification in which the rollers 15, 15, 1G, 16 of the Figs. 1 to 4 construction are omitted, and in order to make the belt hug the crowned table 37, such table is made adjustable vertical-ly by thc use of screws 38 which are threaded through the flanges of the frame members 39, 39. The glass plates 14 are mounted for rocking movement about their lower edges which engage the. glass the same as in the Figs. 1 to 4 construction. but a different means is provided for rocking the sheets. This means includes a frame 40 mounted on wheels 41 on a track 42 extending longitudinally of the table and provided with transverse bars 43 between which the Lipper ends of the sheets lie. The frame 40 is reciprocated by the connecting rod 44 having its left end connected with the crank 45. This crank is driven through the intermediary of suitable connections from the motor 46 which also drives the abrading belt.

IVhat I claim is:

1. In combination in an edge rounding machine, a driven abra-ding belt having one flight extending in a substantially horizontal direction, a support beneath said flight, means for holding the sheets whose edges are edges against movement in the. direction of ,travel of said flight, but free to rock, means -engaging the upper portions of said sheets,

of the belt with their lower edges resting by gravity upon the curved portlon of the belt, means for maintaining such lower edges against movement in the direction of travel of said flight, but free to rock, means engaging the upper portions of said sheets, and means for reciprocating said means longitudinally of the belt to rock the sheets back and forth about their lower edges.

In testimony whereof, I have hereunto subscribed my name this 18thfday of June,

r WILLIAM OWEN.

to be rounded in upright positions transverse to the line of movement of the belt with their lower edges resting by gravity upon said flight, means for maintaining such lower vis 

